The present invention relates, in general, to jump ropes and more particularly, to high speed jump ropes for sustained aerobic exercising.
A detailed analysis of various prior art jump ropes or skip ropes is set out in Everroad U.S. Pat. No. 4,385,759 which is incorporated herein by reference. In the Everroad patent, a jump rope is disclosed in which the handles are hollow cylindrical handle grip members open at each end and in which a pair of shouldered cylindrical bearing members are inserted in each end of the handle grip members. Each bearing member is arranged with a reduced diameter plug portion and has a through hole adapted to receive the skip rope. The rope is threaded through the hole in each bearing member and the free ends of the rope are knotted into a diameter sized to preclude the rope passing back through the hole. The bearing members and the material of the length of the rope have self-lubricating relationship to each other. Nylon, polypropolene, polyvinyl chloride are materials of which the handles and rope are constructed. In the Evenrod jump rope, the knotted end rotates and bears against one of the shouldered cylindrical bearing members, while the remainder of the handle is essentially stationary except for the hand/arm motions of the user. The length of rope can be adjusted by changing the knot position.
There are numerous disclosures in the art of jump ropes having handles with bearings to permit rotation of the rope in the handle. See, for example, U.S. Pat. Nos. 4,101,123; 4,136,866. La Sares U.S. Pat. No. 1,462,088 discloses a jump rope handle in which a hollow handle has a bore in which is loosely mounted a spindle which, in turn, is secured to one end of the rope so that when the rope is rotated, the handle member is essentially stationary and the spindle turns with the rope.
Jump rope or skip rope handles which are adapted to or incorporate rope length adjustment features is disclosed in German Patent 911,713 dated May 17, 1954. In this disclosure, various means are shown for securing an adjustable length of the rope so as to permit easy adjustment of the rope for the user. Similarly, Nissen U.S. Pat. No. 2,869,872 discloses an adjustable handle for a jump rope in which a flexible barrel member has a cap adapted to be positioned in one end of the barrel and a loop is positioned on the cap and extending interiorly of the barrel so that the end of the rope can be passed through a ring on the cap and be doubled-back or looped on itself and thereby wedge the rope in the adjusted position. However, in these disclosures the rope does not rotate in the handles.
The object of the present invention is to provide an improved jump rope, particularly a high rotational speed jump rope for sustained aerobic exercise. The jump rope according to this invention is of a plastic construction which will not corrode. It also provides for instant rope length adjustability which is particularly suited for institutional, health clubs and spas, etc. Moreover, the handles according to the invention accept a broad range of monofilament plastic rope diameters so that they are easily interchangeable so the user can selectively adjust the degree of aerobic or anerobic exercise desired. Moreover, in one adaptation of the invention, more than one rope could be used for a more intense work-out and exercising. Further, the user has many options available for configuration of the jump rope due to the handle design and thus the jump rope can be personalized. Moreover, since the handles are made out of a high density plastic such as nylon, Teflon.TM., Delran.TM., (all are synthetic resin polymers) they are moldable and virtually unbreakable and have high lubricity.
A further feature of the invention is that the "rope", in its preferred embodiment, is not of a woven material but, rather, is a small diameter (preferably 1/4" to 3/8" diameter), smooth, preferably high density polyurethane material or rubber which has a smooth exterior so as to reduce the wind resistance and thus provide for ultrafast rotation. Moreover, because of the handle construction, the rope portion rotates freely with a spindle journaled in the handle thereby permitting this ultra fast rotation. The jump rope is light weight and, finally, incorporates comfortable foam grips so that extended use of the rope is possible. An angulation of rope off the handle transmits the user's rotation power more efficiently and eliminates rope wear-down and deterioration at the handle ends.
According to the invention, the handles are formed from a plastic spindle rod with one or a pair of parallel holes or bores running the entire length thereof and which is mounted or journaled for easy spinning or rotation within a cylindrical handle housing. This allows the rope to rotate substantially free of friction and thus avoid rope deterioration. In the preferred embodiment there are one or more axially extending offset holes in the rod so that the axis of the rope is off-center and locked to act as a crank and help initiate rotation and also, if desired, allow for use of two ropes where a pair of axially extending holes are provided. Preferably however, the extra hole provides a place to put excess rope or could be used as a place to mount the end caps and stabilize the rod within the grip handle. The off-set arrangement acts like a crank and transmits rope or cord rotation energy more efficiently and effectively resulting in a higher cord speed and less wrist fatigue.
Several knotless or knot-free modes of adjusting the length of the rope relative to the handle are disclosed herein. In one embodiment, a rope notch or clamp is built into an end cap. Not only does this feature stabilize the rope but it also sets the rope off at an angle from the handle and has a crank effect which helps initiation of rotation of the rope. A further embodiment of the adjustment feature works simply by inserting the rope in the empty off-set bore hole.
Another adjustment modification feature is the use of cord locks which can be inserted in a large hole of an end cap. The rope would run through the cord lock and out the end of the end cap. Cord locks can also be used outside of the handle separately or in conjunction with each other by being stabilized in the radius curves. In still a further embodiment, a set screw in one of the end caps of the spindle assembly, with or without clamp member or saddle can be used to prevent rope movement relative to the rotary spindle. Finally, the rope can also be adjusted and/or angled in several configurations by inserting it through small holes in the end cap. These adjustment features or embodiments can all be used separately or in conjunction with each other.